Spark plug vapor blasting machine



Dec. 1955 J. M. HELL. z iigg gg SPARK PLUG VAPOR BLASTING MACHINE I Filed Aug. 24, 1953 6 Sheets-Sheet 1 if: a 1

IN VEN TOR. Jfi/Wf M 19/11 Dec. $9 3955 J. M. HELL. Zfiffifig SPARK PLUG VAPOR 'BLASTING MACHINE Filed Aug. 24, 1953 6 Sheets-Sheet 2 IN VEN TOR.

Dec. 6, 1955 J. M. HILL SPARK PLUG VAPOR BLASTING MACHINE 6 Sheets-Sheet 3 Filed Aug. 24, 1953 J. M. HELL Zfifififi g SPARK PLUG VAPOR BLASTING MACHINE Filed Aug. 24, 1953 a sheets-sheet 4 INVENTOR. 5 Jfi/Wfj H71 .45

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Elm. W55 .J. M. HELL. 2 725635 SPARK PLUG VAPOR BLASTING MACHINE Filed Aug. 24, 1953 6 Sheets-Sheet 5 INVENTOR. Jfl/Wif M A424.

@955 J. M. HkLL. Zlfiffifig SPARK PLUG VAPOR BLASTING MACHINE Filed Aug. 24, 1953 6 Sheets-Shea; 6

irmmvw 1 United States Patent SPARK PLUG VAPOR BLASTING MACHINE James M. Hill, San Antonio, Tex.

Application August 24, 1953, Serial No. 376,282

11 Claims. (Cl. 5115) (Granted under Title 35, U. S. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to a new and novel spark plug cleaning apparatus wherein the cleaning operations are fully automatic, necessitating a minimum handling effort on the part of the operator and a saving of time and expense in the process. Moreover the spark plugs in the cleaning process are subjected to precision blasting in groups to insure complete cleaning without damage to the barrels of the plugs. The only handling of the spark plugs by the operator of the apparatus is on loading the machine and unloading. The particular embodiment of the invention described herein will load a minimum of forty spark plugs. However, while the invention is directed to the cleaning of spark plugs, it is readily applicable to other devices requiring similar treatment.

An object of the invention is to provide a new and novel automatic cleaning apparatus.

Another object of the invention is to provide a novel spark plug cleaning apparatus which will automatically and simultaneously clean a multiplicity of spark plugs.

A further object of the invention is to provide a new and novel cleaning apparatus wherein the objects to be cleaned are subjected to precision vapor blasting.

An additional object of the invention is to provide a cleaning apparatus wherein spark plugs may be mounted therein and indexed successively in groups to vapor blasting stations and a cleaning station and to the unloading station in a single cycle of operation.

Another object of the invention is to provide a novel adapter mounting unit for spark plugs so that the barrels may be free from damage in the cleaning process.

A further object of the invention is to provide a novel spark plug cleaning machine employing a system for handling the cleaning solution whereby the solution may be eifectively re-used through several cycles of operation of the machine.

Other objects and advantages of the invention will be readily apparent to those versed in the art from the following description in conjunction with the accompanying drawings wherein:

Fig. l is a partial front view of my novel spark plug cleaning machine showing the loading station.

Fig. 2 shows a partial vertical cross section of my novel machine showing the blow-elf station.

Fig. 3 is a horizontal sectional view taken showing the drive arrangement for the indexing head which suppor the spark plus in groups at respective stages of the cleaning process.

Fig. 3A is a detail showing of the adjustable idler unit shown in Fig. 3.

Fig. 4 is a partial sectional view showing a spark plug adapter unit.

Fig. 4A is a detail showing of a spark plug mounting assembly in its preferred form.

Fig. 5 is a detail showing of the indexing control assembly.

Fig. 6 is a partial detail showing of the buffer unit for interrupting rotation of the indexing head.

Fig. 7 is a horizontal cross-section view of the apparatus showing the respective stations or stages constituting the cleaning process.

Fig. 8 shows the relative fixed nozzle, spark plug alignment at the first vapor blasting station.

Fig. 9 shows the second vapor blasting station details.

Fig. 10 shows the control assembly for the vertically movable vapor nozzles at the second vapor blasting station.

Fig. 11 shows a view of the indexing cam and its association with the cam control of the vertically movable vapor nozzles at the second vapor blasting station.

Fig. 12 is a fragmentary view of the vapor nozzle control unit showing adjustability features.

The invention as shown in the drawings consists of a housing frame 1. Mounted centrally and transversely of the vertical frame is a centrally apertured horizontal mounting plate 2, secured to the frame by any suitable means such as bolts secured to angle'members Welded to the frame as shown particularly in Fig. 2 of the drawings. Secured to the bottom of plate 2 and spaced therefrom is a ring member 3 surrounding the apertured portion of plate 2 and providing therewith a guide slot mountin g for the flange 4 of the spark plug adapter head mounting disc 4 which is rotatably mounted therein. The disc 4 is secured to a hub member 5 by a supporting plate 6 interconnected through the disc 4 to the hub member 5 by threaded bolt members. A centrally apertured indexing head 7 is mounted on the hub member 5 parallel to the disc 4 and bolted to the hub head. A vertically suspended hollow shaft member 8 is mounted in resilient bearings (not shown) in parallel horizontal brackets 9 secured to a support plate 10 connected to the frame 1. The disc 4 has spaced groups of apertures 11 therethrough, the groups being four in number and there being ten apertures in each group. While ten apertures are provided in each group, they may vary as to number in each group. The indexing head 7 has corresponding apertures 12 aligned with the apertures in the disc member. Mounted in each aperture 11 in the disc member is a spark plug adapter unit 13. Mounted in the adapter unit is a hollow support nipple 14 having spaced 0 rings thereon and a portion of reduced outer diameter in which portion is mounted a rubber cup 15 as shown in Fig. 4 of the drawings. The bore of the nipple is restricted adjacent its lower end and has a small screen 16 in front of the restriction. An alternate and preferred form of the nipple 14 shown in Fig. 4A has an upper portion with spaced 0 rings thereon similar to nipple 14 as shown. In addition the nipple 14' has a flange 16' extending therefrom preceding the reduced portion thereof. Mounted on the reduced portion is a hollow rubber spark plug mounting element 17 having a ring portion adapted to abut the flange and tapering to a reduced external diameter with spaced rings thereon integral therewith adapted to securely fit in the barrel section of a spark plug to resist removal after the mounting of a spark plug thereon. The spark plug has a barrel which has a bevel which is adapted to securely seat against the tapered portion of the rubber adapter element 17. The nipple 14 or 14' is mounted in the adapter housing 13 of the adapter unit 13 which has a neck portion by which it is secured in the aperture of the disc member 4. Ahollow spindle member 19 extends into the adapter housing and the nipple has spaced 0 rings 20 mounted thereon by which it is secured to the spindle member 19. The spindle member 19 extends up and through the aligned aperture 12 in the indexing head and is rotatably secured in bearings mounted thereon. A collar 21 is secured to the spindle above the bearings and a pulley wheel 22 is also secured to the spindle for rotation therewith. A tube 23 interconnects the hollow shaft member 8 with each group of spa aim mounting units by means of a connection consisting of a hollow housing 24 connected to the tube and fixed relative to the spindle 19 which is rotatable therein. Each of the spindles in each group has a similar housing 2 associated therewith and there are four equally spaced tubes 23 extending from the hollow shaft f to a central housing 24 in each group and the housings in each group are interconnected by hollow tube members 25. The hollow shaft member 8 has a relatively fixed portion at the upper end thereof to which is connected a vacuum pump which introduces a vacuum through the hollow shaft, tube members 23, through housings 24 by means of tubes 25 into hollow spindles 19 whereby on slipping of a spark plug barrel over a nipple, in the first modification the rubber cup engages the outer surface thereof and the suction in the spindle causes the drawing of the lips of the respective rubber cups into retaining engagement with the spark plugs. The vacuum is only sufficient to hold the plugs and they can be removed by a slight tug.

Whereas in using the preferred form of nipple the suction in the nipple draws the spark plug barrel securely into engagement with the tapered portion of the spark pltw mounting element to provide a sealing engagement therebetween. Similarly as in the first modification the vacuum is such that it only requires a slight tug to remove it.

The indexing head 7 has four equally spaced notches 26 in the periphery thereof. Mounted in each of these notches is a cam stop member 27 secured therein by any suitable means as screws so as to be releasably connected to the indexing head. Mounted on the plate 2 adjacent the disc is a bearing 8 through which extends a camshaft 2). Mounted on the camshaft 29 above the housing and in line with the indexing head is a cam plate 3% having a single contoured projection from an otherwise circular design. A pivot pin 31 is connected to the plate 2 and adjacent the disc 4. Mounted on the pivot pin for rotation thereabout is a cam arm 52. At one end of the arm 32 is mounted a roller 33 cooperatively engaging the cam plate 3% and at the other end of the arm is a bracket 34 depending therefrom. The bracket 34 has a guide hole therein for a plunger member 35 extending from a buffer cylinder 35 supported by arms 36 secured to the cam arm by bolts 37 extending through slotted portions 38 thereof. The slots are to permit relative adjustment of the buffer assembly to the arm for proper engagement of the stop members. A coil spring 39 is mounted in the cylinder 35 in biasing engagement with the plunger member which extends therein to bias it outwardly. Intermediate the ends of the cam arm and secured thereto is a pin til. Connected to the pivot pin 31 is a bar ll. having a vertical member with a hook 42 extending therefrom. A coil spring 42 interconnects the hook 42 and the pin 46. This spring normally tends to bias the arm and associated plunger member into engagement with the stop members on the indexing head. The camshaft 29 has a belt 44 connected to a sheave 43 mounted thereon through which it may be driven by motor 4:; to control the indexing head.

An alternate control to the cam 3i) for the cam arm 32 is shown in Fig. 5 of the drawings and consists of a pin 82 fixed to the cam arm near the buffer end of the cam arm. Connected to the pin is a cable 33 which is connected to one arm of a bell crank lever 84 pivoted on the plate 2 adjacent the arm. A control cable 85 is connected to the other arm of the bell crank lever for manual operation by the operator in the event it is necessary to manually disengage the cam arm from a stop member 27.

Mounted on the support 2 of the housing above the second vapor blasting station is a rectangular framework as shown in Fig. of the drawings. The framework comprises two rear vertical support members 46 4 secured to the support 2 by any suitable means. The two forward vertical members 47 extend through the plate 2 downwardly for connection to the vapor blasting apparatus at the vapor blasting station. Mounted on support 2 and respectively connected to the forward elements are bellows type resilient mountings 48 which tend to limit the forward vertical members in their movements from an upper position. Extending upwardly from the forward members are brackets 49 connected by a reinforcing rod 59. A cable 51 connects the two brackets and extends over a sheave 52 rotatably supported on a bracket 53 connected to the housing to support a counterweight 54, providing a normally resilient balance of the framework. Vertically spaced horizontal bar members 55 and 55 connect the forward and rear members respectively and are pivotally connected to each. Renforcing bars 56 connect the upper pair of horizontal members and lower pair of horizontal members respectively and are in fixed relation thereto. Clamped to the upper of the reinforcing bars 56 is a vertical rectangular linkage 57, its forward vertical member 58 having a depending extension with a roller projection 59 thereon to normally engage a horizontal cam surface 63 mounted on the upper portion of the camshaft 29. A reinforcing bar 61 pivotally connected to the rectangular framework is pivotally connected to a rear vertical member as shown in Fig. 10 of the drawings. The forward-vertically depending member 58 of the rectangular framework is arranged for adjustment as shown in Fig. 12 of the drawin s to insure positive engagement with the horizontal cam surface and camshaft 29. The horizontal cam surface 60 is arranged to function in timed relation to the cam plate Stl. Due to the connection of the rectangular linkage 57 by clamping to the upper transverse connecting bar 56, as the cam surface 64) raises and lowers the rectangular framework, the forward members 47 extending through the support plate 2 by their pivotal relation with respect to the rear vertical support members will move vertically up and down.

To the lower extremities of the forward members 47 are connected forked brackets 62 by pin elements. The brackets have, at their respective forked ends, ring members 62' supporting respectively an abrasive solution manifold and an air manifold which deliver respectively an abrasive liquid solution and compressed air to the vapor blasting nozzles 63 for vapor blasting of the spark plugs.

At the second vapor blasting station in the housing are ten nozzles adjustably supported on the manifolds as shown in Fig. 9 of the drawings each having connections to the manifolds whereby the air drives the abrasive solution outwardly of the nozzle against the spark plugs adjacent the nozzles and in view of the connection of the forward members 47 to the manifolds and connected nozzles there is conjoint movement thereof whereby the nozzles are simultaneously moved vertically of the adjacent spark plugs for precision cleaning as shown in Fig. 9 of the drawings as the cam 60 raises and lowers the rectangular linkage.

Additional manifolds carrying abrasive solution and air are arranged at the second vapor blasting station to deliver to vertical nozzles 64 adjustably supported on the manifolds and directed to the under depending electrode portions of the spark plugs as shown in Fig. 9 of the drawings for simultaneous precision cleaning of each spark plug at the vapor blasting station.

An excess fiow pipe 65 connected to the abrasive solution manifold delivers the excess abrasive solution to the sump 66 arranged in the lower part of the housing.

Mounted on the plate 2 within the frame area is a pulley bracket 67 having a longitudinal horizontal slot 68 in the upper surface. Extending through the slot is a pulley pivot 69 which has a plate 7% at one end thereof beneath the upper plate of the bracket and an idler r wheel 71 at the other end thereof. Washers are inserted to either side of the idler wheel and a nut threaded on the upper end of the pivot pin to retain the idler assembly in assembled relation. A block 72 is connected to the lower end of the pin and threaded longitudinally thereof and arranged within the bracket. Longitudinally of the bracket and mounted therein is a bolt member 73 threadedly engaged in the block element 72. The member 73 is fixed to the bracket so that rotation thereof adjusts the idler assembly longitudinally of the bracket. There are several idler wheels 71 mounted on the plate 2 adjacent the disc 4. A power driven wheel 74 located adjacent the loading station is suspended from a gear housing connected to the frame. A continuous pulley belt 75 extends around the power driven wheel, the outer portion thereof being directed around the successive idler wheels, the inner portion frictionally engaging the outer sides of the spark plug mounting units sheaves inclusive of three fourths thereof only as shown in Fig. 3 of the drawings. The adjustable idler assembly is utilized to adjust the tension on the pulley belt. Accordingly the power driven wheel will cause rotation of the spark plug mountings units which the pulley belt 75 engages and this frictional drive when the cam arm 32 is disengaged from the stop members 27 will induce rotation of the indexing head and the connected disc 4.

There are four stations equally spaced about the housing at the inner side thereof.

The housing frame 1 has an opening in the forward central portion thereof just below the level of the spark plug mounting plate which may be called the first or loading station, shown in Fig. l of the drawings which with the particular practical embodiment of the invention shown is sufiiciently large to present a group of ten spark plug mounting units therein.

Following the loading station there are two vapor blasting stations. The first has fixed horizontal nozzles 76 arranged to blast the lower portions of the spark plugs as shown in Fig. 8 of the drawings. This is necessary to remove the more difficult portion of the scale. At this station are also the abrasive mixture and air manifolds which are shown in Fig. 7 of the drawings on which are supported the ten nozzles arranged to align with the ten spark plugs presented at that station for cleaning. The second vapor blasting station employs the movable nozzle previously described herein with respect to the description of the apparatus of Figs. 9 and 10 of the drawings as well as the fixed nozzles for cleaning the electrode ends of the spark plugs.

The vapor blasting unit at the second vapor blasting station described previously is arranged at the 'rear of the frame opposite the loading station. An access door 77 is arranged in the back side of the frame to the rear of the vapor blasting nozzle units. Sump housing or hopper units 78 are secured to and depend from the mounting I plate 2 and the frame 1. These drain hoppers serve to accumulate the residue from the cleaning solution applied to the plugs and each is provided with a drain hole.

Air is introduced into the hoppers through openings 79 to keep the drained abrasive solution in agitation. This prevents the abrasive from settling out of the solution. A pump is connected to the drain holes 80 in the hoppers so that the abrasive solution may be pumped out and re-used to supply the nozzles for vapor blasting the spark plugs. It is noted again that the spark plugs are held in, a vertical position with the electrode end down and the barrel sealed so that in cleaning the abrasive and water runs out of the cavity of the spark plug so that no hydraulic resistance is built up therein to hinder the efficiency of the blasting of the spark plugs. This is important since in conventional spark plug cleaning units the spark plugs are mounted in horizontal position and the cavity fills up withliquid preventing efiicient cleaning.

At the blow off station intermediate the vapor blasting and unloading station an air pressure line extends hori- 6 zontally across the frame to the rear of the group of spark plugs presented at that station. Vertical tubing connections 81 to a main air line as shown in the drawings in Fig. 2 are connected to the main line to direct air at all portions of the spark plugs. There are ten such connections arranged to align with the ten spark plugs presented at the station. Also a nozzle extends from each of the connections to blow off the electrode end of the spark plug.

A complete cycle of operation of the novel subject invention in its preferred form is as follows. initially ten spark plug adapters are presented at the loading station at the front of the housing. The operator slips the spark plug barrels over each rubber adapter unit extending from the ten spark plug adapters. The spark plugs are initially held thereon by frictional engagement with the rubber mounting units. Suction is then applied through the supporting shaft and spindles to the spark plugs drawing them up into sealing engagement with the tapered portion of the rubber mounting units. During this period the cam arm 32 with its associated buffer means is in engagement with a stop member 27 on the indexing head 7. The motor is energized to drive the continuous pulley belt '75 which by its frictional engagement with the sheaves 22 secured to the spark plug adapter spindles 19 spins such spindles of the sheaves it engages at the two vapor blasting stations and the blowoff station. As can be seen from Fig. 3 of the drawing the spindles at the loading station are free of the drive belt 75. The cam arm 32 may be disengaged from the stop 27 either manually by tripping the arm through the control cable or automatically through energization of the motor 45. In either event as the cam arm is disengaged from the indexing head, the frictional drive of the continuous pulley belt spinning the spark plug adapter spindles as indicated previously will index the indexing head the cam arm buifer member engaging the next stop member 27 and the spark plugs from the loading station are presented at the first vapor blasting station. These spark plugs are now spinning about their own axes due to the engagement of the continuous belt with their sheaves. While the spark plugs are spinning, the vapor blasting nozzles are directing a coninuous stream of abrasive solution at the lower threaded portion of the spark plugs. The lower four threads approximately being the most difficult to clean, this portion of the spark plug receives a precision blasting at this station. As the cam 39 rotates its projecting portion cams the cam arm out of engagement with the stop member 27 and indexes the indexing head presenting the initial group of spark plugs to the second vapor blasting station. At this station as shown in Fig. 9 of the drawings, each spark plug has an adjacent nozzle vertically directed upward to clean the electrode end with an abrasive solution, and simultaneously has a nozzle moving vertically under control of the horizontal cam 60 on camshaft 29 to subject the external surface of each plug to precision blasting. After a further indexing of the spark plug group, they are presented at the blowoff station where air is directed to clean each plug of any abrasive or solution remaining. At this station the cleaning air is directed both upwardly at the electrode end and horizontally from vertical nozzle units having perforations in the sides thereof and directed against the external surface of the spark plugs as they spin.

After air cleaning, the original group of spark plugs are indexed to the loading station again where they may be removed with a slight tug by the operator and dirty spark plugs may replace the clean spark plugs.

it is understood of course that as each set of spark plug adapters is presented at the loading station a set of ten spark plugs is mounted for cleaning. Accordingly, as the original group of spark plugs returns to the loading station, there is a group of ten spark plugs in process of cleaning at each station. Forty spark plugs are accordingly in process of cleaning at one time.

Mounted on camshaft 29'is a transmitter electrically connected to an indicator on the housing so that the particular location at which the cam portion of the cam 30 is located will be indicated so that the operator can follow the functioning of the machine. in the arrangement contemplated the spark plugs are indexed every 30 seconds, but this is merely a selected example and merely illustrative.

The invention resents a novel cleaning apparatus which While directed to the cleaning of spark plugs is readily adapted to other uses which involve spraying or vapor blasting of items which may be mounted on adapters such as utilized in the practical embodiment of the invention described herein and such additional applications will be self evident to those skilled in the art and are within the scope of this invention.

What I claim is:

1. Apparatus for cleaning large groups of spark plugs simultaneously comprising a housing, a rotatable indexing head mounted transversely in said housing, cleaning stations spaced about the indexing head in the housing, spark plug adapter units mounted on said indexing head in equidistantly spaced groups, means for supporting spark plugs in the respec ve adapter units in depending relation for rotation with respect thereto, a control shaft, cam means mounted on said shaft, a cam arm interposed between said cant means and said indexing head, said cam arm being operable on sc on of said control shaft to interrupt the rotation of d indexing head at timed intervals for presenting the groups to successive stations in the housing, fixed vapor olasti nozzles mounted in said housing at a first stat to align with the respective sp plugs presented at the station for initial cleaning, vertically movable spark plug vapor bias nozzles presented at a succeeding station n the housing vapor blasting the spark plugs for precision blasting thereof, a second cam means .lOllliifiLl on said shaft, means connecting said second cant means and said vertically movable nozzles for vertical movement thereof relative to the respectively aligned spark plugs at said timed intervals and means providing horizontal and vertical air jets at the individual spark plugs at a blow off station in said housing.

2. Apparatus for precision cleaning a multiplicity of spark plugs simultaneously comprising an indexing head mounted for rotation about its central axis, spark plug mounting means mounted on said indexing head arranged in equidistantly spaced groups, belt drive means continuously rotating spark plugs mounted in said mounting means simultaneously in all but one of said groups, vapor blasting station and blow oft station spaced about the indexing head having spray nozzles to align with the respective spark plugs, means interrupting the rotation or". the indexing head at timed intervals to a predetermined position thereof with respect to said stations to align individual spark plugs with respective nozzles, means automatically relea' mg said interrupting means at timed intervals, said belt drive means effecting the indexing of a group of spark plugs to a predetermined station on the release of the interrupting means.

3. Apparatus for cleaning a multiplicity of spark plugs simultaneously comprising an indexing head for mounting spaced groups of spark plugs thereon for rotation with the indexing head about its central axis, cleaning stations arranged circumferentially of the indexing head arranged for the alignment of spark plugs thereon with individual blasting nozzles arranged at the espective stations, stop means for holding said indexing head in a series of predetermined positions mounted in spaced relation thereon to present the spaced groups of spark plugs successively at predetermined cleaning stations, cant controlled interrupter means for sequentially engaging and releasing said indexing head from a predetermined position, means continuously rotating the spark plugs While at the cleaning stations, said means continuously rotating the spark plugs at the cleaning stations etlecting the indexing of the indexing head to a succeeding predetermined position from a predetermined position on release of the stop means by said interrupter means.

4. Apparatus for mounting spark plugs for precision cleaning without damage to the barrel comprising a housing, a hollow shaft mounted in said housing, an indexing head connected to said shaft for rotation therewith, spaced groups of spark plug adapters mounted in said head equally spaced from the central axis thereof, hollow spindles in said adapters, conduit means connecting each of said spindles and said shaft, spark plug mounting means fixed in said spindles including a resilient portion tapered to a reduced diameter and arranged for frictional engagement with spark plug barrels and means for applying suction through said shaft, spindles and spark plug mounting means to the spark plugs whereby the spark plugs are drawn into sealing engagement with the resilient tapered portion of said spark plug mounting means.

5. An apparatus for mounting spark plugs for clean ing without damage of the barrels comprising an adapter housing, a hollow spindle mounted therein for rotation with respect thereto, a hollow nipple connected to the spindle and having a flange thereon adjacent a portion of reduced diameter, a resilient spark plug mounthig element mounted on said portion or" reduced or meter abutting the flange and having a conical tapered portion, the portion of reduced diameter on the resilient element having means thereon adapted to frictionaliy retain the barrel of a spark plug mounted thereon and suction means connected with the hollow spindle whereby on application of suction the spark plug is drawn into fixed engagement with the resilient element with the mouth of the spark plug barrel in sealing relation with the tapered portion of the resilient element.

6. in a spark plug precision cleaning apparatus, a frame, a mounting plate rotatable in the frame, spaced groups of hollow spark plug mounting elements arranged in said plate 'circurnferentially thereof, spaced cleaning stations in said housing, indexing means operatively connected to said plate operable to index the plate at timed intervals so as to bring the groups to successive cleaning stations, and suction means associated with the bore of each of the mounting elements to directly engage and to releasably retain the spark plugs mounted thereon for cleaning.

7. in a spark plug cleaning apparatus in combination with an apertured plate for mounting spark lug mountlog units in groups, spark plug adapter units each comprising a hollow spindle, a housing for said spindle adapted for mounting in an aperture in said mounting plate, a hollow resilient cup mounted on the spindle adjacent the lower end thereof, and suction means connected to the hollow spindle whereby on sliding a spark plug barrel over the spindle and applying suction thereto the resilient cup lips will sealingly engage the outer surface of the spark plug barrel to prevent entrance of foreign matter therein.

8. In an apparatus for cleaning spark plugs a housin a mounting plate for spark plugs arranged therein for rotation about a vertical axis, means for rotating said plate operatively connected thereto, means associated with said plate operable to interrupt the rotation thereof at timed intervfls, means for mounting the spark plugs in groups in depending relation with respect to said plate so as to be rotatable with respect to the plate, a loading station, vapor blasting station, and blow old station arranged successively about and within the housing, said means for rotating said plate constituting means for directly rotating said spark plugs at the vapor blasting and blow oftstations and operative to index the plate to successive stations in the housing on time-d release of the interrupting means, an air manifold and abrasive solution manifold arranged at the vapor blasting station with common nozzles to align with spark plugs presented. at that station and. for movement vertically of the spark plugs for vapor blasting during an interruption of rotation of said plate, means for moving said nozzles vertically for precision blasting of the spark plugs operable in conjunction with and in timed relation to said interrupting means, a hopper in said housing below the spark plugs to receive overflow and drained abrasive solution on vapor blasting, means to continuously agitate the solution in the hopper and means to direct such solution for re-use in the abrasive solution manifold.

9. In a spark plug cleaning apparatus, a frame, cleaning stations spaced about the frame, a rotatable mounting plate arranged in the frame, spark plug mounting means mounted in said mounting plate in spaced groups, suction means connected with said spark plug mounting means adapted to releasably retain spark plugs thereon, driving means associated with said spark plug mounting means adapted to provide continuous rotation thereof, means operatively interconnecting said frame and said mounting plate to automatically interrupt said mounting plate at predetermined spaced positions thereof intermediate the successive spaced groups of spark plug mounting units, means for automatically releasing said interrupting means at timed intervals, each interruption presenting the spaced groups of spark plug mounting units successively to a loading, vapor blasting, blow off, and unloading station.

10. The structure as set forth in claim 9 and blasting means arranged at the vapor blasting station and operatively associated with said interrupting means to move vertically of the spark plugs on the mounting units presented at that station during an interruption while directing an abrasive cleaning solution at the outer surface thereof.

11. Apparatus for precision cleaning spark plugs without damage to the barrel comprising a housing, a hollow shaft mounted in said housing, an indexing head connected to said shaft for rotation therewith, spaced groups of spark plug adapters mounted in said head equally spaced from the central axis thereof, hollow spindles in said adapter, conduit means connecting each of said spindles and said shaft, spark plug mounting means fixed in said spindles including a resilient portion tapered to a reduced diameter and arranged for frictional engagement with spark plug barrels, means for applying suction through said shaft, said spindles, and said spark plug mounting means to the spark plugs whereby the spark plugs are brought into sealing engagement with the resilient tapered portion of said spark plug mounting means, blasting means spaced about said housing arranged for successive fixed alignment with successive groups of spark plugs, and means for continuously rotating the spark plugs with their mounting means while in alignment with the blasting means, said means for continuously rotating the spark plugs constituting the means to index said indexing head.

References Cited in the file of this patent UNITED STATES PATENTS 1,317,809 Motz Oct. 7, 1919 1,875,994 Davis Sept. 6, 1932 1,887,395 Billings Nov. 8, 1932 2,345,884 Powers Apr. 4, 1944 2,351,272 Le Tourneau June 13, 1944 2,365,152 Stearman Dec. 19, 1944 2,393,762 Emerson Jan. 29, 1946 2,454,158 Gossard Nov. 16, 1948 2,505,422 Michaels Apr. 25, 1950 2,575,631 Link Nov. 20, 1951 

